pathfinding modifiers are currently a lower priority than terrain are, navmesh wise meaning its causing inconsistencies as right now the priorities are Terrain → PathfindingModifiers → Parts respectively.
The files below, including repro file, perfectly display the issue at hand. The humanoid on terrain seems to ignore the Deadzone (which also isnt displayed in visualization) whereas part materials work as intended.
Scripts that handle pathfinding are located inside of the characters for convenience and are set to math.huge cost on Deadzone.
This behavior happens in BOTH PathfindingUseImprovedSearch Enabled and Disabled
repro pathfinding modifier.rbxl (103.4 KB)
Expected behavior
I expect pathfindingModifiers to be the highest priority so that it functions accordingly on any environment, as stated in the original announcement